In the last decade, the photovoltaic (PV) business has grown at an approximate annual growth rate of greater than 40%. Though the cost of PV generated electricity has come down significantly and is rapidly becoming competitive with conventional means of electricity generation, challenges still lie in further lowering the cost of PV systems. About 50% of the cost of a typical PV system is due to the cost of solar panels that are assembled by connecting a number of solar modules in a desired series or parallel circuit. The remaining 50% cost contribution is due to the balance of the system (BOS) consisting of mounting structures, cables, inverters, permitting and installation.
Currently, wafer based technology of crystalline silicon (c-Si) solar cells dominates the global market with greater than 80% of the market share. However, the cost associated with the production of c-Si modules is an impediment for the production of low-cost solar cells. Thin film solar cell technologies offer the potential of achieving lower manufacturing costs. A generic thin film solar cell typically may include a stack of a number thin films deposited on a substrate, a metallic back contact, a semiconductor absorber layer that effectively absorbs the sunlight, a semiconductor buffer layer that forms a p-n junction, and a transparent conducting oxide (TCO) as the top current collecting layer. In the family of thin film compound solar cells of Group 12-16 (e.g., CdTe), Group 11-13-16 (e.g., CuInGaSe2-CIGS), and Group 11-12-14-16 (e.g., Cu2ZnSnS4-CZTS) are various absorber layers, CdS, ZnS, CdZnS, ZnSe, In2S3 are examples of buffer layers and ZnO,SnO2 and ITO (indium tin oxide) are examples of transparent conducting oxide. However, most of the current methods and systems for forming thin film cell solar cells are plagued by one or more challenges, including high production cost, poor efficiencies, complicated manufacturing equipment, etc.
Accordingly, improved methods, systems, and apparatuses are needed.